Crank bearing bottom bracket

[edge]

2006  Gary Fisher  Piranha BS:6102 crank is a fc-m410

Hi i am new here and need a lil help with my bike i just brought to ride to work on, so when i ride i can feel that the crank bearings need replacing or bottom bracket i am not a bike mechanic, and i am struggling to find what bottom bracket i need to fix this issue, any help will be much appreciated thanks for your time and reading,
 
  Adam.

[nfmisso]

Shimano recommends a 118mm BB axle length for the FC-M410 crankset.  You need a square taper BB with 118mm axle that fits your bike.  Most likely the size spec will be 68x118, but it might be 73x118.  You need to measure the width of the BB shell of your bike frame to know for sure.

Once you have the measurement, you can get your new BB.  A Shimano UN26 is a safe choice.

And you need to tools to do the job - which cost more than the parts.  If you are not planning on working on many bikes, you'll be ahead by having your local shop do it.  

[nfmisso]

Most likely given that it is a 2006 bike, Adam is dealing with a seal cartridge bearing bottom bracket., not cups.  Thus not really serviceable......

That said,  you are correct, it could just need to be properly torqued - same tools required.

On my PDG 70, I sensed something wrong, pulled out the original BB, inspected and re-installed, this time torquing things to spec.  Fixed.  The PDG 70 has a Shimano UN70 68x122 BB - 1992 vintage original equipment.  

[nordog]

What if you have a seized cup type BB like I have at the moment to deal with, the old spanners are to short to reach pass the shaft of the BB. This means I must make my own out of some hard steel with a fair bit of leverage to the handle. Can you come up with a better idea, I have tried some heat to expand the housing like I did on five bikes with sealed bearings one bike took two of us to get it to shift even with heat, there all fine now.

[edge]

Thanks for your help Nigel i have got the new parts last week and got it all fitted by my bike shop,
now i have a nice smooth ride again thanks so much for all your help